1. Field of the Invention
This invention relates to a concrete panel having tiles preattached and driven on its surface used for the interior and exterior finishes of a building.
2. Description of the Prior Art
Conventionally were used a precast concrete panel having tiles driven for the interior and exterior finishes of a building, and a light weight concrete panel having tiles driven on a sheet of concrete (GFRC) reinforced by glass fibers. However, in the case of the former concrete panel, the thickness of a lining base material concrete is required to be 100-150 mm and the weight of same required to be about 250-350 Kg/m.sup.2 for providing a predetermined performance so that cost for transporting and mounting the panel becomes high and the weight of the whole building is increased disadvantagously. Also in the case of the latter GFRC panel, the thickness of lining GFRC base material is generally 10-20 mm and the weight including tiles 100-150 Kg/m.sup.2 so that the panel can be lightened compared with conventional concrete panels. However, since this GFRC panel uses prepared mortar rich in cement for the base material, it has larger rate of drying shrinkage compared with common concrete (common concrete=(5-8).times.10.sup.-4, GFRC.apprxeq.15.times.10.sup.-4). Thus, the panel having tiles driven has large dimensional variation of GFRC at the rear surface, warping and twist, compared with the surface tile after manufacturing so that the tile is cracked by these warping and twist and the tile tends to be disadvantageously exfoliated.
To prevent large drying shrinkage of GFRC, the ratio of the shrinkage may be reduced by high temperature and pressure steam curing (generally steam with max. temperature and pressure of about 180.degree. C. and 10 atmospheric pressure respectively is used). However, even if alkali resisting glass fibers were used for reinforcing glass fibers, it could not be cured by high temperature and pressure since it is remarkably degraded by temperature of 80.degree. C. or more.